American Girl made a carrier for girls that fits two dolls. At the American Girl Doll Store they have doll-sized carriers for $10.
The purple and pink bag says American Girl on the front and is made out of very nice materials.
It has these little white elastic straps inside which I’m assuming is for strapping the dolls in, although mine fit perfectly without the straps.
The dolls love their new ride!
Have fun with your doll!